<template>
  <div :class="{active:isActive}" class="share-dropdown-menu">
    <div class="share-dropdown-menu-wrapper">
      <span class="share-dropdown-menu-title" @click.self="clickTitle">{{ title }}</span>
      <div v-for="(item,index) of items" :key="index" class="share-dropdown-menu-item">
        <a v-if="item.href" :href="item.href" target="_blank">{{ item.title }}</a>
        <span v-else>{{ item.title }}</span>
      </div>
    </div>
  </div>
</template>

<script>
  export default {
    props: {
      items: {
        type: Array,
        default: function () {
          return []
        }
      },
      title: {
        type: String,
        default: 'vue'
      }
    },
    data() {
      return {
        isActive: false
      }
    },
    methods: {
      clickTitle() {
        this.isActive = !this.isActive
      }
    }
  }
</script>

<style lang="scss">
  $
  n:

  9
  ;
  /
  /
  和items.length 相同
$ t:

  .1
  s

  ;
  .share-dropdown-menu {
    width: 250px;
    position: relative;
    z-index: 1;
    height: auto !important;

  &
  -title {
    width: 100%;
    display: block;
    cursor: pointer;
    background: black;
    color: white;
    height: 60px;
    line-height: 60px;
    font-size: 20px;
    text-align: center;
    z-index: 2;
    transform: translate3d(0, 0, 0);
  }

  &
  -wrapper {
    position: relative;
  }

  &
  -item {
    text-align: center;
    position: absolute;
    width: 100%;
    background: #e0e0e0;
    color: #000;
    line-height: 60px;
    height: 60px;
    cursor: pointer;
    font-size: 18px;
    overflow: hidden;
    opacity: 1;
    transition: transform 0.28s ease;

  &
  :hover {
    background: black;
    color: white;
  }

  @for $i from 1 through $n {
  &:nth-of-type(#{$i}) {
    z-index: -1;
    transition-delay: $ i *$ t;
    transform: translate3d(0, -60px, 0);
  }
  }
  }
  &
  .active {

  .share-dropdown-menu-wrapper {
    z-index: 1;
  }

  .share-dropdown-menu-item {

  @for $i from 1 through $n {
  &:nth-of-type(#{$i}) {
    transition-delay: ($ n -$ i) * $ t;
    transform: translate3d(0, ($ i -1) *60px, 0);
  }
  }
  }
  }
  }
</style>
